# from tkinter import *
# class Application(Frame):
#     def __init__(self, master=None):
#         Frame.__init__(self, master)
#         self.pack()
#         self.createWidgets()

#     def createWidgets(self):
#         self.helloLabel = Label(self, text='Hello, world!')
#         self.helloLabel.pack()
#         self.quitButton = Button(self, text='Quit', command=self.quit)
#         self.quitButton.pack()

# app = Application()
# # 设置窗口标题:
# app.master.title('Hello World')
# # 主消息循环:
# app.mainloop()


